Grenade.



J.'B. SEMPLE.

GRENADE.

APPLICATION FILED AUG.2, 1915.

1 ,2@3,62 r Patented Oct. 31, 1916.

WITNESS S JOHN B. SEMPLE, OF SEWICKLEY, PENiYSYLVANIA.

GRENADE.

To all whom it may concern:

Be it known that 1, JOHN B. SEMPLE, residing at Sewickley, in the county of Allegheny and State of Pennsylvania, a citizen of the United States, have invented or discovered certain new and useful .Impr'ove ments in Grenades, of which improvements the following is a specification.

My invention relates to improvements in grenades'such as arenow used in warfare by dropping from air-craft, and my object is to produce a grenade in which efi'ectiveness andcheapness of manufacture are combined, in highest degree.

In the accompanying drawings Figure 1 shows my improved grenade in side elevat ion; Fig. 2 is a similar view on larger scale, the length of the whole being diminished by the breaking away of part; Fig. 3 is a view partly in side elevation and partly in longitudinal section of a portion of the body of the grenade; and Fig. 4 is a .view such as Fig. 3, illustrating a modification in structure.

The first feature of my invention to which I desire to call attention is the great relative length of the grenade. The body proper of the grenade is, as compared with grenades heretofore known, exceedingly long andslender.

The primitive grenadethe bombis spherical in shape, just as the primitive projectilethe cannon ball'is spherical.

The cannon ball has been elongated to cylindrical form with this end in view that, when fired from a rifled gun and so caused to rotate on its axis, it will hold its course more surely, fiy farther, and penetrate deeper. And the bomb has been elongated, first to pear shape (or pomegranate shapep hence the name grenade), then to cylindrical shape, that, when properly weighted and provided with steering vane or tail, it

may surely fly on its major axis and strike on its head; for the mechanically operating fuse (as distinguished from the time fuse which it has largely displaced) and by which the grenade is exploded, for proper and certain functioning, requires that the grenade be so controlled in flight. Neither projectilesto be fired from rifled guns nor grenades have heretofore been elongated to accomplish other ends than these; and these ends are accomplished, and completely accomplished, in elongation in which the length becomes three or four times greater sweeps wide areas.

Specification of Letters Patent. P t t d O t, 31,1916. Application filed August 2, 1915. Serial No. 43,117.

than the diameter. nor projectile constructed, or even proposed, prior to my invention, in which the length was more than five times greater than the diameter.

The grenade ofmy invention, as distin- I know of no grenade gu'ished from the grenade of-the prior art,

jected missiles produced by explosion are for themost part soon stopped by surface irregularities, my grenade on explosion And in this connection I desire to point out that this is not a case in which actual dimensions may be adopted at will; it is not a case in. which the riorart structures may be magnified to a egree such that they will stand as high as mine.

Quite aside from any question of economy,

the limitations imposed upon the grenade designerlimitations such as the carrying capacity of an aeroplane, the muscular strength of the user, eta-forbid any such magnification as that just suggested. The extreme attenuation which characterizes the grenade of my invention then relates itself in the matter of dimension to actual physical conditions: the depth of furrows in plowed fields, the height of curbstones in city streets, and such like matters. That there is in this matter of actual dimension a point of practical value is evidenced by earlier efforts to overcome the difliculty with grenades such as have previously been made: jumping bombs are grenadeswhich on striking reboundand which after rebounding explode while still in the air. Another expedient is to equip a grenade with a suspended weight which, falling faster than the grenade, shall strike the ground first, and on striking shall efiect the explosion of the high explosives. My grenade built fortythree inches long and an inch and three quarters in diameter has missile-forming wall of steel about three-eighths of an inch thick and a chamber for the burster charge of a scant inchin diameter. A column of black powder an inch in diameter would be utterly incapable of bursting, and driving out in a shower of missiles steel walls three eighths of an inch thick, or of any considerable thickness. But even with the use of high explosives the great attenuation which characterizes the grenade of my invention has this result: the force of explosion is not exerted to fragment the casing transversely 7 into pieces of adequate missile forming dimensions. A steel caslng having an internal diameter of an inch with Walls three eighths of an inch thick will be burst by the det onation 'of a body of high explosive filling the bore, but it will be torn into long shreds or splinters, and not into suitable grenade missiles.

There is a critical point, not capable (because of the variables involved) of precise definition, but still clearly discernible-a critical point in the development of this idea of attenuation, beyond which (but for my invention) a grenade may not be elongated;

column of burster charge will be ineffective,

overcoming the strength of the relatively heavy walls, to fragment the casing and project the pieces with requisite momentum. The critical point first mentioned above I term, in the ensuing claims, the critical point in the matter of longitudinal fragmentation.

of the grenade.

My invention consists in a grenade of the extreme tenuity which I have described,

whose casing is discontinuous in the direction of its length. The missile-forming body is cut through, at intervals such as to aifordproper dimension of the missiles, in planes of cutting transverse to the length Thus no disruptive strain longitudinally of the structure is requisite, but only the transverse strain Which shall tear ,the casing apart in longitudinally extending breaks and project the pieces in substantially horizontal directions.

I am well aware that both projectiles and grenades have heretofore been contemplated in which the missile forming portions of the casing are built up of ballsor rings,

forehand their actual size.

which are of course longitudinally discontinuous; and I am aware also of the expedient of carameling the casingthat is to say, scoring it with longitudinal and transverse grooves. But these expedients have been adopted, not to supply or correct or overcome a deficiency in the power of the burster charge, but rather to correct the bad effect of too much power in the explosive. The tendency is to a pulverizing of the easingbreaking of it down to sand or granules and so rendering it ineffective as missile material. On this account the missile-forming material has heretoforebeen made discontinuous or places of disruption have been predetermined. But never before has this idea-of the breaking of the longitudinal continuity of the casing been brought into coordination with the idea of a grenade of extreme length, to accomplish the practical and valuable ends which I attain and have here described.

My grenade is constructed in the manner sile-forming portion of the structure is formed is the relatively thin walled casing 3. Ordinarily this casing will take the form of a steel tube or pipe an inch in diameter and formed of material about one thirty-second of an inch thick; and, as noted above, this pipe will be about forty-three inches long. But the specific figures are given by way of illustration merely, not by way oflimitation; they may be departed from widely. Within this casing 3 is contained the burster charge A. Around this casing 3 is applied the material which is to be fragmented by explosion and driven in fragments in all directions. This missile-forming material is applied in a succession of encircling bands, either in a helix 4, as shown in Fig. 8, or in a succession of separate rings 4, as shown in Fig. 4. In minuter detail this missileforming material may be such and so fabri cated as desired, to meet the ends in view. In my preferred construction, with effectiveness and economy both in mind, I employ a rolled steel rod three eighths of an inch in diameter, applied as a helix; and,'to the end .that the missiles may be of more certainly uniform size, this steel rod is weakened by notches at suitably recurrent intervals, as indicated in the drawings at a, b, 0, etc. It is manifest that in the size of the rod employed and in the space interval of the successive weakening notches, the constructor may insure beforehand. uniformity in the size of the missiles and may determine be- It' is not indeed requisite that my wrapped-on helix or succession of rings which on explosion form the missiles be scored or weakened by cuts or grooves, for the force of explos1on 1s radial from the center and must inevitably tear each encircling band into parts and drive those fragments in substantially radial directions.

It is to be remarked of the grenade which" I have now described that it is a grenade which is cylindrical and elongate in such marked degree that on explosion relatively loss of effectiveness), but substantially all will be driven in substantially horizontal lines-the direction most desired.

In other respects the grenade shownin the drawings possesses known features. The tail 5 is a cloth tail of frusto-conical shape, and open ended, and is secured to the upper or posterior end of the grenade by a frame 6. The tail of course serves to bring the grenade to'and maintain it more certainly in vertical position as it falls. The loop 7 of cord or such like material is provided as a means by which a cotter pin 8 may be drawn, which when drawn'releases a Wind- 'Wheel 9 and allows it to rotate as the projectile falls. The rotation of this Wind-wheel effects the arming of the fuse, whichnormally is unarmed, so that when the grenade strikes the armed fuse will function and detonation of the burster charge will ensue.

It will be understood on reading the foregoing description that certain features of my invention are not limited in their applicability to grenades as such but, are applicable generally to projectiles of other sorts as well as to grenadesand I have drawn the ensuing claims accordingly.

I claim as my invention L 1. An aeronautical bomb attenuated beyond the critical point inthe matter of longitudinal fragmentation and including a missile-forming casing longitudinally sub divided atintervals corresponding to missile dimenslons. I

my hand.

said bodyfsaid missile-forming helix being weakened at intervals and possessing at such points of Weakness a strength to resist bursting less than the disruptive strain there exerted on the explosion of the said body of explosive material.

5. A projectile including in its structure a helix of missile-forming material weakened at intervals in its length and'surrounding a burster-charge chamber;

6. A projectile including in its structure a helix of notchedsteel rod surrounding a burster-charge chamber.

7. A grenade comprising an attenuated central burster charge, a wall surrounding said charge and comprising a longitudinally discontinuous but circumferentially continuous body of missile-forming material, the disruptive' capacity of the unit quantity of said charge, which, when detonated, acts upon a circumferential unit length of the missile-forming material, being greater than the resistance of said Wall of material to dis ruption and lateral projection.

8. A'projectile including in its structure a tubular chamber and a helix of notched steel rod surrounding said chamber.

In testimony whereof I have hereunto sei JOHN B.- SEMPLE. 

